The general aim of Core B, the Data Collection Core, is to provide the necessary tools and methods to collect reliable, consistent, accurate data of all types for the AgeWise Program. Its activities will span a number of types of data, including self-report and clinician-rated questionnaires, diaries, polysomnographic sleep studies, core body temperature recordings, measures of immune and neuroendocrine function, and integrated sleep and functional imaging data. Core B will also support activities conducted in a variety of settings, including subjects' homes, offices of AgeWise staff, the sleep laboratory, and primary care offices. They key functions of Core B are embodied in a set of clinical, physiological, and laboratory measures that constitute the AgeWise Battery of assessments, or Agebat, which will be used by each of the five Projects. Specific Aims for Core B are: Aim 1: To provide tools and methods for the collection of self-report and clinician-rated questionnaire data and diary instruments. Aim 2. To provide tools and methods for the collection of polysomnographic (PSG) sleep data in the laboratory setting and in subjects' homes. Aim 3: To provide tools and methods for the collection of other objective indices of health, such as vital signs, nutritional status, physical activity, neuroendocrine and immune function measures. Aim 4: To ensure the reliability and consistency of data collection and measurement through a rigorous program of quality control, calibration, and inter-rater reliability checks. In order to achieve these aims, Core B will review each Project's operations manual to ensure consistency in study procedures; convene monthly meetings of investigators, consultants, data collection and data management staff to review data collection procedures and potential problems; establish regular consistency and inter-rater reliability checks on clinical and laboratory data; and oversee equipment calibration and maintenance procedures. Core B will also interact with both other Cores in the AgeWise Program. Specifically, Core B will draw administrative support from Core A (Administration and Subject Recruitment- Monk), and will contribute Agebat resources to the recruitment and screening function of Core A. Core B will provide data regarding data collection procedures to NIA progress reports and to manuscripts written by AgeWise Program investigators. Core B will also interact regularly with Core C (Data Management and Statistics - Mazumdar, Grochocinskl) by providing raw data for data base entry and management, and for subsequent statistical analyses.